Paper slitter with dust removal vacuum device



June 2, 1964 P. J. LINK ETAL 3,135,151

PAPER SLITTER WITH nus? RBMQVAL VACUUM DEVICE 3 Sheets-Sheet 1 FiledMarch 6, 1961 TEL/ 3,135,151 PAPER SLITTER WITH DUST REMOVAL VACUUMDEVICE Filed March 6; 1961 June 2, 1964 P. J. LINK ETAL 3 Sheets5heet 2June 2, 1964 p |NK ETAL 3,135,151

PAPER SLITTER WITH DUST REMOVAL VACUUM DEVICE 3 Sheets-Sheet 3 FiledMarch 6, 1961 United States Patent 3,135,151 PAPER SLITTER WITH DUSTREMOVAL VACUUM DEVICE Peter J. Link, Neenah, and Harvey F. Metzig,Appleton, Wis, assignors to Kimberly-Clark Corporation, Neenah, Wis., acorporation of Delaware Filed Mar. 6, 1961, Ser. No. 93,690 7 Claims.(Cl. 83168) Our invention relates to machines for slitting or cuttingwebs, particularly paper webs.

Slitters comprising a pair of opposite rotating wheels in shearingcontact with each other are in common usage. When these slitter wheelsare used with common printing or writing paper that is coated with theusual mineral or clay coating, it has been found that flecks and duct ofthis coating are formed by the slitter, and such debris is extremelydeleterious for subsequent usage, such as for printing. Some of thisdebris is thrown upwardly while some of it adheres to the cut webs, andit is an object of the present invention to provide improved dustremoval mechanism for removing both the dust thrown into the air as wellas the dust that adheres to the paper.

More particularly, it is an object of the present invention to providean improved dust removing hood that is effective directly on the cutwebs with a relatively high vacuum and low rate of air flow and which iseffective on one of the slitter wheels with a relatively low vacuum anda high rate of air flow.

In a preferred form, the hood, according to the invention, has a portionembracing one of the slitter wheels and a perforate shoe that is incontact with the web adjacent the slit provided by the slitter wheels.Due to internal partitioning of the hood according to the invention, arelatively high vacuum from a vacuum conduit is effective on the shoeand thus on the Web while a relatively low vacuum, with a correspondinghigh air flow, is effective around one of the slitter wheels.

The invention consists of the novel constructions, ar-

,rangements, devices and methods to be hereinafter described and claimedfor carrying out the above stated objects and such other objects as willbe apparent from the following description of a preferred form of theinvention, illustrated with reference to the accompanying drawings,wherein:

FIG. 1 is a side view of a slitter for paper webs including a dustremoving hood which incorporates the principles of the invention andwhich includes a dust removing shoe for slidingly contacting the paperweb in the vicinity of the slit;

FIG. 2 is an end view of the slitter; FIG. 3 is a sectional view on anenlarged scale taken on line 3-3 of FIG. 1;

.several views.

Referring now to the drawings, the illustrated slitting device may beseen to comprise a top slitter blade or wheel and a bottom slittercylinder or wheel 11. The

wheel 10 and cylinder 11 are beveled on their edges as shown in FIG. 3to havea shearing action between them when they are rotatively driven.The slitter cylinder 11 is mounted on suitable framing (not shown) andis driven 3,135,151 Patented June 2, 1964 by an electric motor 12 alsomounted on the framing. The top slitter blade is rotatably mountedthrough intermediate connecting mechanism with respect to a stationarysupport which is in the form of a shaft 13.

The slitter blade 10 is carried by an arm 14 that is fixed on a shaft15. The shaft '15 extends through a yoke 16 that is in turn carried byanother, larger, yoke 17 that embraces the shaft 13. The shaft 15 isthreaded on its upper end, and an adjusting nut 18 positions the shaft15, arm 14 and slitter blade 10 in desired vertical positions. A clampscrew 19 extends through ears 20 provided on the two ends of the yoke 16for tightening the shaft 15 within the yoke 16 in properly verticallyadjusted position; and a clamp screw 21 extends through two ears 22provided on the ends of the yoke 17 for fixing the yoke 17, shaft 15,arm 14 and slitter wheel 10 in proper rotative positions about thesupport shaft 13. With the parts in their preferred adjusted positionsas illustrated, the shaft 15 extends approximately vertically, and thearm 14 is so located vertically that the slitter blade 10 overlaps theslitter cylinder 11 to a slight extent.

A dust collecting hood 23 is disposed about the slitter wheel 10. Thehood 23 is swingably mounted with respect to the shaft 15 by means of abolt 24 that extends through parts of a clamp 25 that embraces the shaft15. A bracket 26 is fixed to the clamp 25 and shields the side of thewheel 10 opposite the hood 23. Swinging movement of the hood 23 withrespect to the shaft 15 is limited by means of abutting projections 27and 28 fixed with respect to the bracket 25 and hood 23 respectively.

The hood 23 embraces the wheel 10 and has side portions or flanges 29and 30 extending parallel to and alongside the Wheel 10 on oppositesides of the wheel. The side portions or flanges 29 and 30 are joined bymeans of a rounded rim portion 31. A tubular conduit 32 is connected tothe inner cavity of the hood 23, and a partition 33 is provided withinthe hood having its end lying approximately on the longitudinal centerline of the conduit 32.

The hood 23 is provided with a downwardly extending conduit 34 connectedwith the conduit 32 and disposed partially below the upper end of thepartition 33. The conduit 34 enlarges on its lower end to a relativelybroad conduit 35, and a shoe 36 fits .in the conduit 35. The shoe 36 hasa longitudinally extending groove or slot 37 extending through it whichconnects with the conduits 35 and 34 and is provided on its bottomsurface with tongues '38 separated by grooves 39 which extend slantwisewith respect to both the transverse and longitudinal axes of the shoe.

A pair of brushes 40 and 41 are provided on opposite sides of theconduit 35. Each of the brushes is fixed within a brush holder 42. Eachof the holders 42 has slots 43 through it, and a cap screw 44 extendsthrough each of slots 43 and into the. shoe 36 for fixing the shoe 36and brushes 40 and 41 with respect to the sides of the conduit 35. Aslide piece 45 embraces a part of the shoe 36. The slide piece 45 hasinturned flanges 46 fitting in side slots 47 in the shoe, and the slidepiece 45 is provided with end lugs 48 and 49, as shown. The slide piece45 may be moved longitudinally of the shoe 36 simply by sliding thefianges 46 in the slots 47 to more or less cover the bottom surface ofthe shoe 36 and more or less cover the slot 37 on the bottom surface ofthe shoe 36.

The conduit 32 is connected through a flexible hose 5i) to a suitablesource of vacuum 51.

In operation, a paper web 52 is moved between the slitter wheels 10 and11, being suitably supported prior to and after passing between thewheels 10 and 11 by any suitable rolls or other supports (not shown).The motor 12 drives the slitter wheel 11, and the two wheels 10 and 11have a shearing action, shearing strips of the web 52 apart, such as toremove an edge strip 52a from the remainder of the web 52 (see FIG. 4).The shearing action is particularly by virtue of the tapered cuttingedges on the wheels and 11 previously mentioned. The wheel 11 ispreferably driven by the motor 12 to have a slightly faster speed at itsperiphery than the speed at which the paper 52 is passed between thewheels 10 and 11, such differential of speed being, for example, about10 percent. The wheel 10 is driven due to friction with the wheel 11,and it thus has about the same speed as the wheel 11. Although the web52 can be of any suitable paper, the invention is particularly concernedwith paper that is coated with the usual conventional mineral or claycoatings, such paper being particularly useful as printing or writingpaper. Coating flecks and dust are caused by the shearing action of thewheels 10 and 11 on such coated paper, and unless this residue isremoved, it can well cause difficulties in subsequent usage of the papersuch as in printing operations. Some of this dust is thrown upwardlyfrom the paper and would be distributed over quite a wide area of thepaper while the rest of the dust would accumulate along the slit 52b inthe paper and would adhere to the paper due to static electricity. Thehood 23 connected to the source of vacuum has the function of collectingthe dust and residue from the slitting operation and removing it fromthe paper.

The sides 29 and 30 and peripheral rim portion 31 embrace the upperWheel 10, and the hood 23 thus collects the dust that is thrown upwardlyby the slitting operation. This dust is drawn through the conduit 32 andhose 50 to the vacuum source 51. The shoe 36 has the function ofremoving the dust that adheres along the slit 525 from the paper. Theside flange 48 of the piece 45 is so positioned, assuming that the edgeportion 52a is being removed as scrap from the main portion of the paperby the slitting operation, so that the slit 52b lies along the outeredge of the flange 48. It is desired that the shoe 36 shall be effectiveto provide a vacuum action on only the useable part of the paper 52, andthe shoe 45 in its illustrated position thus closes off the slot 37 inthe part of the shoe 36 embraced by the slide piece 45. There thus is nolarge air flow or loss of vacuum in that part of the shoe 36 that doesnot cover a part of the paper 52.

The main portion of the web 52 to the left of the flange 48 as seen inFIG. 4, passes under the bottom surface of the shoe 36, and air flowsthrough the slantwise extending grooves 39 between the ribs 38 and intothe slot 37 of the shoe, drawing the dust on the main portion of the Web52 at its edge along the slit 52b into the shoe and thus into theconduit 32 and hose 50 to the vacuum source 51. The brushes 40 and 41are effective on the sheet 52 before and after the shoe 36 along theslit 525 as the sheet passes beneath the shoe for assisting indislodging flecks of dust that adhere to the web due to staticelectricity, and the slantwise extending ribs 38 also have this dustdislodging function. Although the web 52 is shown as having an edgeportion 52a slit from it by the illustrated slitting mechanism, it willbe understood that a paper web may be split along a median line toprovide webs of substantial Width. In this case, the slide 45 would notbe used and would be disassociated from the shoe 36 so that aboutone-half of the shoe 36 on one side of the slitter wheel 10 would beeffective on one of the resulting webs and the other side of the shoe onthe other side of the wheel 10 would be effective on the other web.There would be no necessity for blocking off a portion of the bottomsurface of the shoe 36 in this case, since one of the split webs wouldperform the function of closing off the right portion of the shoe (asseen in FIG. 4), and, in fact, the function of the shoe in cleaning bothof the split webs would be desired.

It is contemplated that the paper web may contact the bottom surface ofthe shoe 36 due only to the force of the vacuum applied to the webthrough the branch conduit 34 and shoe 36. No support for the paper webbeneath the shoe 36 is necessary.

It has been found very desirable that the vacuum applied to the shoe 36through the branch conduit 34 shall be higher than the vacuum applied tothe hood 23 as a whole between the side flanges 29 and 30. The partition33 has been provided for this effect. The partition 33 extendsapproximately to the center line of the conduit 32, so that the vacuumeffect in the lower half of the conduit 32 is effective substantiallysolely on the branch conduit 34 and thus on the shoe 36. Since thebottom of the shoe 36 is substantially closed by either the two splitWebs provided by the slitter wheels or alternately by a single web 52,together with the slide 45, there is a relatively small flow of airupwardly through the branch conduit 34, and due to such restriction inthe flow of air through the shoe 36 and due also to the partition 33,the vacuum within the branch conduit 34 and in the shoe 36 remainsrelatively high. Since there is little restriction to the flow of airaround the slitter wheel 10 and into the hood 23 between the sideflanges 29 and 30, there is a relatively large flow of air between theside flanges 29 and 30 and into the conduit 32 above the partition 33.The relatively high vacuum effective on the shoe 36 and the relativelylow vacuum with a large rate of air flow around the slitter wheel 10 andbetween the side flanges 29 and 30 have been found to provide effectiveremoval of the dust thrown upwardly as well as effective removal of thedust that adheres tothe paper in the vicinity of the slit particularlydue to static electricity.

If it is desired to change the particular slitter wheel 10 that is beingused, the hood 23 may be moved upwardly to permit ready removal of thewheel 10 from its arbor. In order to accomplish this, the stud 24 isloosened and the hood 23 may then be swung upwardly about the stud 24.The lugs 27 and 28, as has been previously mentioned, limit the downwardswinging movement of the hood to a proper position as illustrated whenthe hood is returned to embrace a slitter wheel 10.

Most of the dusting problem in the illustrated slitter is, of course, onthe upper surface of the paper 52, since the dust tends to settle bygravity. There can be, of course, a minor accumulation of dust on thelower surface of the sheet 52 and, if desired, a hood 23 can also belocated about the bottom slitter wheel 11. The shoe 36 of the lower hood23 would be positioned approximately below the shoe 36 for the upperhood 23, and the lower hood 23 could be fixed with its clamp 25embracing a lower vertical shaft 53 suitably fixed with respect to theframing of the slitter by any suitable means (not shown).

We wish it to be understood that the invention is not to be limited tothe specific constructions and arrangements shown and described, exceptonly insofar as the claims may be so limited, as it will be understoodto those skilled in the art that changes may be made without departingfrom the principles of the invention. In particular, it will beunderstood that although the slitter mechanism has been described inparticular for use in connection with paper Webs, the slitter mechanismmay also be used on a sheet material other than paper, such as inconnection with plastics, non-woven fabrics, plywood, board, etc.Insofar as the drive for the cylinder 11 is concerned; obviously, inlieu of the electric motor 12, the cylinder 11 may be mechanicallydriven such as by an air motor, or by means of a belt connected with asuitable prime mover, etc.

Although the hood 23 has been described in connection with the shearingwheels 10 and 11, it will be understood that such a hood may also beuseful in connection with other types of slitters, such as those usingfixed upstanding slitter blades, for example. The partition 33 has beendisclosed to provide the relatively high vacuum in the shoe 36 and therelatively low vacuum about the wheel 10; however, it will be understoodthat actually two different prime sources of vacuum, such as twodifferent vacuum pumps, may be used instead, one being connected to drawair from about the wheel and the other being connected to the shoe 36,and the claims are not to be limited to the partition 33 or the likeexcept insofar as they may be specifically so limited. It will also beobvious that, although the shaft is illustrated as being vertical inconnection with a horizontally movable web 52, if the Web is arranged totravel other than horizontally, likewise the shaft 15 will be moved fromits vertical position to accommodate the changed direction of travel ofthe web.

We claim:

1. In sheet cutting mechanism, means for severing sheet material along aline of cut into a plurality of parts including a rotatable cuttingwheel having its edge passing through the sheet material and forming theline of cut, means for providing a relatively low vacuum about saidwheel for drawing off air carried cutting dust from about the wheel, andmeans for providing a relatively high vacuum along the line of outbetween the parts of the sheet material for drawing oif cutting dustcarried by the sheet material along the line of cut.

2. In sheet cutting mechanism, means for severing sheet material along aline of cut into a plurality of parts including a rotatable cuttingwheel having its edge passing through the sheet material and forming theline of cut, a hood partially embracing said wheel and including aconduit for connecting the hood with a source of vacuum for drawing offair carried cutting dust from about the wheel, said hood being providedwith a portion including a perforate shoe for contacting the sheetmaterial along the line of cut for drawing off cutting dust carried bythe sheet material along the line of cut, and a partition in said hoodfor partially isolating said shoe with respect to the remainder of thehood embracing the wheel and providing a direct connection of said shoeto said conduit so that a higher vacuum is effective on said shoe thanabout said cutting wheel.

3. In sheet cutting mechanism, means for severing sheet material along aline of cut into a plurality of parts including a rotatable cuttingwheel having its edge passing through the sheet material and forming aline of cut, a hood partially embracing said cutting wheel and connectedby means of a conduit with a source of vacuum for drawing off aircarried cutting dust from about the wheel, a branch conduit connectingwith said first named conduit, a perforate shoe in said branch conduitand adapted to contact the sheet material along the line of cut fordrawing off cutting dust carried by the sheet material along the line ofcut, a partition within said hood for partially isolating said branchconduit with respect to the remainder of the hood embracing the wheeland to provide a substantially direct connection between the shoe andsaid first named conduit so that the vacuum applied to the said materialby the shoe is greater than the vacuum about said wheel provided by thehood and, a brush mounted on said branch conduit for brushing the sheetmaterial passing in contact with said shoe for dislodging dust along theline of cut.

4. In a method of drawing oif cutting dust in the vicinity of arotatable cutting wheel having its edge passing through sheet materialfor forming a line of cut in the sheet material, providing a relativelylow vacuum about the wheel for drawing off air carried cutting dust fromabout the wheel, and providing a relatively high vacuum along the lineof cut for drawing off cutting dust carried by the sheet material alongthe line of cut.

5. A hood for a rotatable cutting wheel which wheel is adapted to haveits edge pass through sheet material for forming a line of cut in thesheet material, said hood comprising a yoke shaped portion for partiallyembracing the cutting wheel and connected to a vacuum conduit fordrawing off air carried cutting dust from about the wheel, said hoodbeing provided with a perforate shoe connected with said conduit adaptedto contact the sheet material as the cutting wheel severs the sheetmaterial, and a partition within said hood for partially isolating saidshoe with respect to the part of the hood embracing the cut-- ting wheeland for providing a direct connection between said shoe and conduit sothat a higher vacuum is eifective on the shoe than within the part ofthe hood embracing the cutting Wheel.

6. In sheet cutting mechanism, a cutting wheel, a rotatable shaft onwhich the cutting wheel is mounted for driving the wheel so that itsedge passes through the sheet material for forming a line of cut as thesheet material moves relative to the wheel from one side of said shaft 7to the other, and a hood connected with a source of vacuum and embracingsaid wheel on One side of said shaft for drawing off air carried cuttingdust from about the wheel, said hood having a hollow part connected withsaid vacuum source through the hooded and depending from the hood on thesame side of said shaft as the hood, said hollow part having a flatsurface with an orifice therethrough under which the sheet materialalong said out line passes for drawing oif cutting dust carried by thesheet material along the line of cut.

7. In sheet cutting mechanism, a cutting wheel, a rotatable shaft onwhich the cutting wheel is mounted for driving the wheel so that itsedge passes through the sheet material for forming a line of cut as thesheet material moves relative to the wheel from one side of said shaftto the other, a hood connected with a source of vacuum and embracingsaid wheel on one side of said shaft for drawing off air carried cuttingdust from about the wheel, and a perforate shoe positioned on the sameside of said shaft as the hood and depending from said hood so as to beconnected thereby to said source of vacuum and so as to contact thesheet material along said line of cut for drawing oif cutting dustcarried by the sheet material along the line of cut.

References Cited in the file of this patent UNITED STATES PATENTS1,359,718 McGuire Nov. 23, 1920 1,637,060 Simons July 26, 1927 1,819,131Spanel Aug. 18, 1931 1,876,337 Mead Sept. 6, 1932 1,883,327 Becker Oct.18, 1932 1,939,925 Schwartz Dec. 19, 1933 1,986,726 Grozier Jan. 1, 19352,585,186 Taylor Feb. 12, 1952 2,675,575 Dow Apr. 20, 1954 2,807,086Watkins Sept. 24, 1957

5. A HOOD FOR A ROTATABLE CUTTING WHEEL WHICH WHEEL IS ADAPTED TO HAVEITS EDGE PASS THROUGH SHEET MATERIAL FOR FORMING A LINE OF CUT IN THESHEET MATERIAL, SAID HOOD COMPRISING A YOKE SHAPED PORTION FOR PARTIALLYEMBRACING THE CUTTING WHEEL AND CONNECTED TO A VACUUM CONDUIT FORDRAWING OFF AIR CARRIED CUTTING DUST FROM ABOUT THE WHEEL, SAID HOODBEING PROVIDED WITH A PERFORATE SHOE CONNECTED WITH SAID CONDUIT ADAPTEDTO CONTACT THE SHEET MATERIAL AS THE CUTTING WHEEL SEVERS THE SHEETMATERIAL, AND A PARTITION WITHIN SAID HOOD FOR PARTIALLY ISOLATING SAIDSHOE WITH RESPECT TO THE PART OF THE HOOD EMBRACING THE CUTTING WHEELAND FOR PROVIDING A DIRECT CONNECTION BETWEEN SAID SHOE AND CONDUIT SOTHAT A HIGHER VACUUM IS EFFECTIVE ON THE SHOE THAN WITHIN THE PART OFTHE HOOD EMBRACING THE CUTTING WHEEL.